Controlling partner partitions in a clustered storage system

ABSTRACT

A rack-power control module (RPC) module is used for allowing a local storage partition, located on a local server, for controlling a destination storage partition, located on a destination server, by piggybacking commands on power alerts issued by the RPC module in a clustered storage system. The commands are sent from the local storage partition to the RPC module, where the commands are RPC commands and include a destination server identification (ID) and payload data that includes a hypervisor command containing a command type, a subtype, and a destination ID. The RPC module then parses the commands received from the local storage partition.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application is a Continuation of U.S. patent application Ser. No.13/1732,483, filed on Jan. 2, 2013, now U.S. Pat. No. 9,342,249, thecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates in general to computers, and moreparticularly to controlling partner partitions in a clustered storagesystem in a computing environment.

Description of the Related Art

In today's society, computer systems are commonplace. Computer systemsmay be found in the workplace, at home, or at school. Computer systemsmay include data storage systems, or disk storage systems, to processand store data. A storage system may include various storage components,such as one or more disk drives configured in a storage environment. Forexample, the storage environment may include a number of disk drivesimplemented in an array, such as a Redundant Array of Independent Disks(RAID) topology, to provide data security in the event of a hardware orsoftware failure. The storage environment may also include other storagecomponents, such as controllers and interfaces to manage the flow ofdata. Moreover, the computer system may include a complex dataprocessing system or computing environment. A computer system mayinclude a complex data processing system or computing environment. Thedata system often requires computational resources or availabilityrequirements that cannot be achieved by a single computer. Thus a needexists for controlling partner partitions in a clustered storage system,in a computing environment when a computer is architecturally arrangedto form a cluster for sharing workload. More specifically, a need existsfor a partition on a server to interact with a partner partition onanother server where the partner partition is off, not responding,and/or not yet running the storage driver code.

SUMMARY OF THE DESCRIBED EMBODIMENTS

In one embodiment, a method is provided for controlling partnerpartitions in a clustered storage system, in a computing environment. Arack-power control module (RPC) module is used for allowing a localstorage partition, located on a local server, for controlling adestination storage partition, located on a destination server, bypiggybacking commands on power alerts issued by the RPC module in aclustered storage system. The commands are sent from the local storagepartition to the RPC module, where the commands are RPC commands andinclude a destination server identification (ID) and payload data thatincludes a hypervisor command containing a command type, a subtype, anda destination ID. The RPC module then parses the commands received fromthe local storage partition.

In addition to the foregoing exemplary method embodiment, otherexemplary system and computer product embodiments are provided andsupply related advantages. The foregoing summary has been provided tointroduce a selection of concepts in a simplified form that are furtherdescribed below in the Detailed Description. This Summary is notintended to identify key features or essential features of the claimedsubject matter, nor is it intended to be used as an aid in determiningthe scope of the claimed subject matter. The claimed subject matter isnot limited to implementations that solve any or all disadvantages notedin the background.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the advantages of the invention will be readilyunderstood, a more particular description of the invention brieflydescribed above will be rendered by reference to specific embodimentsthat are illustrated in the appended drawings. Understanding that thesedrawings depict embodiments of the invention and are not therefore to beconsidered to be limiting of its scope, the invention will be describedand explained with additional specificity and detail through the use ofthe accompanying drawings, in which:

FIG. 1 is a block diagram illustrating a computing system environmenthaving an example storage device in which aspects of the presentinvention may be realized;

FIG. 2 is a block diagram illustrating a hardware structure of datastorage system in a computer system in which aspects of the presentinvention may be realized;

FIG. 3 is a flowchart illustrating an exemplary method for controllingpartner partitions in a clustered storage system;

FIG. 4 is a block diagram illustrating an exemplary alternative blockdiagram of a storage system connected to a SAN in which aspects of thepresent invention may be realized;

FIG. 5 is a flowchart illustrating an alternative exemplary method forcontrolling partner partitions in a clustered storage system.

DETAILED DESCRIPTION OF THE DRAWINGS

As previously mentioned, a computer system may include a complex dataprocessing system or computing environment. The data system oftenrequires computational resources or availability requirements thatcannot be achieved by a single computer. In such cases, a number ofcomputers and storage systems may be architecturally arranged to form acluster for networking several data processing systems together for thepurpose of providing continuous resource availability and for sharingworkload. Network services may be provided using a server cluster inwhich multiple server services are connected together in a storage areanetwork (SAN) configuration. The cluster may be one node or, morecommonly, a set of multiple nodes coordinating access to a set of sharedstorage subsystems typically through the storage area network (e.g., aset of shared storage subsystems). Within these enterprise storagesystems (e.g., clustered storages system environments) there aretypically multiple servers in a cluster to provide redundancy and/orperformance.

As will be described herein, in one embodiment, for error recovery orcode maintenance, a partition running on a server is required for beingable to control a partner partition running on another server in thecluster storage environment, such as rebooting, powering off, orpowering on the partner partition, which may be included in anothercluster storage server. Hence, it is required that the servers to beconnected together via some clustering hardware such as ethernet,Infiniband, etc., that can be managed by a hypervisor and provideinterface for the partition to ask the hypervisor on one server tocommunicate with the hypervisor on another server to perform the partnercontrol command. In one embodiment, dedicated hardware is required aswell as a clustering interface that hypervisor needs to manage. In oneembodiment, the present invention utilizes a rack power control facilitythat often exists in an Enterprise storage system to provide poweralerts to the servers. One or more commands are piggybacked on thisalert system to allow one partition in a server to control a partnerpartition running on another server. Piggybacking is similar tohitchhiking—two different and separate entities that share the same orsimilar destination and one of them uses the other as a transportationmethod towards the destination. Here, piggybacking is used to describethe process in which one command, emitted by one partition “rides” apower alert issued by the rack power control facility to reach a partnerpartition destination, for controlling the partner partition.

Accordingly, in one embodiment, by way of example only, a rack-powercontrol module (RPC) module is used for allowing a local storagepartition, located on a local server, for controlling a destinationstorage partition, located on a destination server, by piggybackingcommands on power alerts issued by the RPC module in a clustered storagesystem. Hence, the RPC module is used as a way for a partition in aserver to inform/control another partition (e.g., a partner partition)running on another server.

Turning now to FIG. 1, exemplary architecture 10 of a computing systemenvironment is depicted. The computer system 10 includes centralprocessing unit (CPU) 12, which is connected to communication port 18and memory device 16. The communication port 18 is in communication witha communication network 20. The communication network 20 and storagenetwork may be configured to be in communication with server (hosts) 24and storage systems, which may include storage devices 14. The storagesystems may include hard disk drive (HDD) devices, solid-state devices(SSD) etc., which may be configured in a redundant array of independentdisks (RAID). The operations as described below may be executed onstorage device(s) 14, located in system 10 or elsewhere and may havemultiple memory devices 16 working independently and/or in conjunctionwith other CPU devices 12. Memory device 16 may include such memory aselectrically erasable programmable read only memory (EEPROM) or a hostof related devices. Memory device 16 and storage devices 14 areconnected to CPU 12 via a signal-bearing medium. In addition, CPU 12 isconnected through communication port 18 to a communication network 20,having an attached plurality of additional computer host systems 24. Inaddition, memory device 16 and the CPU 12 may be embedded and includedin each component of the computing system 10. Each storage system mayalso include separate and/or distinct memory devices 16 and CPU 12 thatwork in conjunction or as a separate memory device 16 and/or CPU 12.

FIG. 2 is an exemplary block diagram 200 showing a hardware structure ofa data storage system in a computer system according to the presentinvention. Host computers 210, 220, 225, are shown, each acting as acentral processing unit for performing data processing as part of a datastorage system 200. The cluster hosts/nodes (physical or virtualdevices), 210, 220, and 225 may be one or more new physical devices orlogical devices to accomplish the purposes of the present invention inthe data storage system 200. In one embodiment, by way of example only,a data storage system 200 may be implemented as IBM® System Storage™DS8000™. A Network connection 260 may be a fibre channel fabric, a fibrechannel point to point link, a fibre channel over ethernet fabric orpoint to point link, a FICON or ESCON I/O interface, any other I/Ointerface type, a wireless network, a wired network, a LAN, a WAN,heterogeneous, homogeneous, public (i.e. the Internet), private, or anycombination thereof. The hosts, 210, 220, and 225 may be local ordistributed among one or more locations and may be equipped with anytype of fabric (or fabric channel) (not shown in FIG. 2) or networkadapter 260 to the storage controller 240, such as Fibre channel, FICON,ESCON, Ethernet, fiber optic, wireless, or coaxial adapters. Datastorage system 200 is accordingly equipped with a suitable fabric (notshown in FIG. 2) or network adaptor 260 to communicate. Data storagesystem 200 is depicted in FIG. 2 comprising storage controllers 240 andcluster hosts 210, 220, and 225. The cluster hosts 210, 220, and 225 mayinclude cluster nodes.

To facilitate a clearer understanding of the methods described herein,storage controller 240 is shown in FIG. 2 as a single processing unit,including a microprocessor 242, system memory 243 and nonvolatilestorage (“NVS”) 216. It is noted that in some embodiments, storagecontroller 240 is comprised of multiple processing units, each withtheir own processor complex and system memory, and interconnected by adedicated network within data storage system 200. Storage 230 (labeledas 230 a, 230 b, and 230 n in FIG. 3) may be comprised of one or morestorage devices, such as storage arrays, which are connected to storagecontroller 240 (by a storage network) with one or more cluster hosts210, 220, and 225 connected to each storage controller 240.

In some embodiments, the devices included in storage 230 may beconnected in a loop architecture. Storage controller 240 manages storage230 and facilitates the processing of write and read requests intendedfor storage 230. The system memory 243 of storage controller 240 storesprogram instructions and data, which the processor 242 may access forexecuting functions and method steps of the present invention forexecuting and managing storage 230 as described herein. In oneembodiment, system memory 243 includes, is in association with, or is incommunication with the operation software 250 for performing methods andoperations described herein. As shown in FIG. 2, system memory 243 mayalso include or be in communication with a cache 245 for storage 230,also referred to herein as a “cache memory”, for buffering “write data”and “read data”, which respectively refer to write/read requests andtheir associated data. In one embodiment, cache 245 is allocated in adevice external to system memory 243, yet remains accessible bymicroprocessor 242 and may serve to provide additional security againstdata loss, in addition to carrying out the operations as described inherein.

In some embodiments, cache 245 is implemented with a volatile memory andnon-volatile memory and coupled to microprocessor 242 via a local bus(not shown in FIG. 2) for enhanced performance of data storage system200. The NVS 216 included in data storage controller is accessible bymicroprocessor 242 and serves to provide additional support foroperations and execution of the present invention as described in otherfigures. The NVS 216, may also referred to as a “persistent” cache, or“cache memory” and is implemented with nonvolatile memory that may ormay not utilize external power to retain data stored therein. The NVSmay be stored in and with the cache 245 for any purposes suited toaccomplish the objectives of the present invention. In some embodiments,a backup power source (not shown in FIG. 2), such as a battery, suppliesNVS 216 with sufficient power to retain the data stored therein in caseof power loss to data storage system 200. In certain embodiments, thecapacity of NVS 216 is less than or equal to the total capacity of cache245.

Storage 230 may be physically comprised of one or more storage devices,such as storage arrays. A storage array is a logical grouping ofindividual storage devices, such as a hard disk. In certain embodiments,storage 230 is comprised of a JBOD (Just a Bunch of Disks) array or aRAID (Redundant Array of Independent Disks) array. A collection ofphysical storage arrays may be further combined to form a rank, whichdissociates the physical storage from the logical configuration. Thestorage space in a rank may be allocated into logical volumes, whichdefine the storage location specified in a write/read request.

In one embodiment, by way of example only, the storage system as shownin FIG. 2 may include a logical volume, or simply “volume,” may havedifferent kinds of allocations. Storage 230 a, 230 b and 230 n are shownas ranks in data storage system 200, and are referred to herein as rank230 a, 230 b and 230 n. Ranks may be local to data storage system 200,or may be located at a physically remote location. In other words, alocal storage controller may connect with a remote storage controllerand manage storage at the remote location. Rank 230 a is shownconfigured with two entire volumes, 234 and 236, as well as one partialvolume 232 a. Rank 230 b is shown with another partial volume 232 b.Thus volume 232 is allocated across ranks 230 a and 230 b. Rank 230 n isshown as being fully allocated to volume 238—that is, rank 230 n refersto the entire physical storage for volume 238. From the above examples,it will be appreciated that a rank may be configured to include one ormore partial and/or entire volumes. Volumes and ranks may further bedivided into so-called “tracks,” which represent a fixed block ofstorage. A track is therefore associated with a given volume and may begiven a given rank.

The storage controller 240 may include a rack power control module 255,a hypervisor, and a LPAR 259. The rack power control module 255, thehypervisor 257, and the LPAR 259 may work in conjunction with each andevery component of the storage controller 240, the hosts 210, 220, 225,and storage devices 230. The hypervisor 257 supports multiple instancesof one or more operating systems and/or operating system partitions onthe shared computational resources of the distributed data processingclusters/nodes of system 200 (e.g., hosts, 210, 220, and 225). Thehypervisor 257 communicates with system-level service processor of thesystem 200, which is responsible for booting a system and for monitoringthe availability of the shared resources 210, 220, and 225. A logicalpartitioning option (LPAR) within a data processing system (platform)allows multiple copies of a single operating system (OS) or multipleheterogeneous operating systems to be simultaneously run on a singledata processing system platform. A partition, within which an operatingsystem image runs, is assigned a non-overlapping sub-set of theplatform's resources. These platform allocable resources include one ormore architecturally distinct processors with their interrupt managementarea, regions of system memory, and I/O adapter bus slots. Thepartition's resources are represented by its own open firmware devicetree to the OS image. Each distinct OS or image of an OS running withinthe platform are protected from each other such that software errors onone logical partition cannot affect the correct operation of any of theother partitions. This is provided by allocating a disjoint set ofplatform resources to be directly managed by each OS image and byproviding mechanisms for ensuring that the various images cannot controlany resources that have not been allocated to it. Furthermore, softwareerrors in the control of an OS's allocated resources are prevented fromaffecting the resources of any other image. Thus, each image of the OS(or each different OS) directly controls a distinct set of allocableresources within the platform. To create and maintain separation betweenthe partitions within each system 200 of a clustered storage system isthe use of a firmware component referred to as a hypervisor 257.

Also, in one embodiment, the hypervisor 257 may be installed on eachserver and implemented as firmware. The hypervisor 257 may perform anumber of functions and services for operating system images (not shown)to create and enforce the partitioning of logically partitioned platform259. Firmware is “hard software” stored in a memory chip that holds itscontent without electrical power, such as, for example, read-only memory(ROM), programmable ROM (PROM), erasable programmable ROM (EPROM),electrically erasable programmable ROM (EEPROM), and non-volatile randomaccess memory (non-volatile RAM). The hypervisor 257 may manage theallocation of computer resources. For example, the hypervisor 257 mayallocate a first block of memory to a first virtual computer and asecond block of memory to a second virtual computer. In addition, thehypervisor may allow two or more operating systems (OS) to execute onvirtual computers. A context of each OS may run on separate virtualcomputers. The hypervisor 257 may manage the switching of contextsbetween each OS. The partitioning of the computer hardware into multiplevirtual computers can significantly reduce the cost of providingmultiple computers. Also server virtualization may user the hypervisor257 and the OS may be executed on a LPAR in the virtual machine. LPAR isthe abbreviation of a logical partition 259, and is a logical hardwareresource that is based on a physical hardware resource.

Each distributed data processing node/hosts, 210, 220, and 225 isassociated with a service processor/microprocessor 242, e.g., serviceprocessors, each of which is responsible for booting its associated nodeand for assisting system-level service processor in monitoring each ofthe nodes; a service processor/microprocessor 242 may be associated witha node through a variety of physical connections to its associated node,e.g., the service processor's hardware card may attach to a PCI bus. Itshould be noted that each node may have a plurality of serviceprocessors/microprocessors 242, although only one service processorwould be responsible for booting its associated node. The rack powercontrol module 255, the hypervisor 257, the LPAR 259 may be structurallyone complete module or may be associated and/or included with otherindividual modules. The rack power control module 255, the hypervisor257, and the LPAR 259 may also be located in the cache 245 or othercomponents.

The storage controller 240 includes a control switch 241 for controllingthe fiber channel protocol to the host computers 210, 220, 225, amicroprocessor 242 for controlling all the storage controller 240, anonvolatile control memory 243 for storing a microprogram (operationsoftware) 250 for controlling the operation of storage controller 240,data for control, cache 245 for temporarily storing (buffering) data,and buffers 244 for assisting the cache 245 to read and write data, acontrol switch 241 for controlling a protocol to control data transferto or from the storage devices 230, the rack power control module 255,the hypervisor 257, and the LPAR 259, in which information may be set.Multiple buffers 244 may be implemented with the present invention toassist with the operations as described herein. In one embodiment, thecluster hosts/nodes, 210, 220, 225 and the storage controller 240 areconnected through a network adaptor (this could be a fibre channel) 260as an interface i.e., via at least one switch called “fabric.”

In one embodiment, the host computers or one or more physical or virtualdevices, 210, 220, 225 and the storage controller 240 are connectedthrough a network (this could be a fibre channel) 260 as an interfacei.e., via at least one switch called “fabric.” In one embodiment, theoperation of the system shown in FIG. 2 will be described. Themicroprocessor 242 may control the memory 243 to store commandinformation from the host device (physical or virtual) 210 andinformation for identifying the host device (physical or virtual) 210.The control switch 241, the buffers 244, the cache 245, the operatingsoftware 250, the microprocessor 242, memory 243, NVS 216, rack powercontrol module 255, the hypervisor 257, and the LPAR 259 are incommunication with each other and may be separate or one individualcomponent(s). Also, several, if not all of the components, such as theoperation software 250 may be included with the memory 243. Each of thecomponents within the devices shown may be linked together and may be incommunication with each other for purposes suited to the presentinvention.

As mentioned above, the rack power control module 255, the hypervisor257, and the LPAR 259 may also be located in the cache 245 or othercomponents. As such, one or more of the rack power control modules 255,the hypervisor 257, and/or the LPAR 259 may be used as needed, basedupon the storage architecture and users' preferences.

FIG. 3 is a flowchart illustrating an exemplary method for controllingpartner partitions in a clustered storage system. For controllingpartner partitions in a clustered storage system, the method 300 begins(step 302) by using a rack-power control module (RPC) module forallowing a local storage partition, located on a local server, forcontrolling a destination storage partition, located on a destinationserver, by piggybacking a plurality of commands on power alerts issuedby the RPC module (step 304). The method 300 ends (step 306).

Turning now to FIG. 4, FIG. 4 is a block diagram illustrating anexemplary alternative block diagram of a storage system connected to aSAN in which aspects of the present invention may be realized. Thestorage system 400 contains an array of hard-disk drives (HDDs) and/orsolid-state drives (SDDs) such as a RAID array. As shown, the storagesystem 400 includes a hardware management controller (HMC) 403, astorage controller 404, one or more switches 406, and one or morestorage devices 408, such as hard disk drives 408 or solid-state drives408. The storage controller 404 may enable one or more hosts (e.g., opensystem and/or mainframe servers) to access data in one or more storagedevices 406. In selected embodiments, the storage controller 404includes one or more local servers 410. The storage controller 404 mayalso include host adapters 412 and device adapters 413 to connect tohost devices and storage devices 408, respectively. Multiple localservers 410A, 410B may provide redundancy to ensure that data is alwaysavailable to connected hosts.

Thus, if one server 410A fails, the other servers 410B may remainfunctional to ensure that I/O is able to continue between the hosts andthe storage devices 408. This process may be referred to as a“failover.” Then, for example, using the rack-power control module (RPC)module, the local storage partition, located on a local server, controlsa destination storage partition, located on a destination server. Thecommands, issued by the local storage partition, piggybacks the commandson power alerts issued by the RPC module. One example of a storagecontroller 404 having architecture similar to that illustrated in FIG. 4is the IBM DS8000™ enterprise storage system. The DS8000™ is ahigh-performance, high-capacity storage controller providing diskstorage that is designed to support continuous operations. The DS8000™series models may use IBM's POWER5™ servers 410A, 410B, which may beintegrated with IBM's virtualization engine technology. Nevertheless,the software update apparatus and methods disclosed herein are notlimited to the IBM DS8000™ enterprise storage system 400, but may beimplemented in comparable or analogous storage systems, regardless ofthe manufacturer, product name, or components or component namesassociated with the system. Furthermore, any system that could benefitfrom one or more embodiments of the invention is deemed to fall withinthe scope of the invention. Thus, the IBM DS8000™ is presented only byway of example and is not intended to be limiting.

In selected embodiments, each server 410 may include one or moreprocessors 414 (e.g., n-way symmetric multiprocessors) and memory 416.The memory 416 may include volatile memory (e.g., RAM) as well asnon-volatile memory (e.g., ROM, EPROM, EEPROM, hard disks, flash memory,etc.). The volatile memory and non-volatile memory may, in certainembodiments, store software modules that run on the processor(s) 414 andare used to access data in the storage devices 408. The server 410 mayhost at least one instance of these software modules. These softwaremodules may manage all read and write requests to logical volumes in thestorage devices 408. The memory 416 includes a volatile cache 418 andnon-volatile storage 420. Whenever a host (e.g., an open system ormainframe server) performs a read operation, the server 410 may fetchdata from the storages devices 408 and save data in the cache 418 in theevent the data is required again. If the data is requested again by ahost, the server 410 may fetch the data from the cache 418 instead offetching it from the storage devices 408, saving both time andresources. Storage system 400 also includes a power subsystem 430 thatprovides power to the various components of the system. Power subsystem430 comprises multiple redundant rack power controllers (RPC) 432 andmultiple redundant primary power supplies (PPS) 434. The RPC is acommunications controller for the power subsystem of the DS8000enterprise storage system. The RPC formats and routes data between thevarious entities of the power subsystem and the local servers. ThePrimary Power Supply (PPS) is a modular power supply, providing power(e.g, 11.5 kW) for use by all the various components of the DS8000enterprise storage system, including the local server, drives, RPCs,batteries, etc.

To facilitate the rapid transfer of large amounts of data, the HMC 403,storage controller 404 (and all of its components), switches 406 andstorage devices 408 are all interconnected via high-throughput channels440 such as Ethernet or Fibre Channel. The RPC modules and PPSs areinterconnected to each other and local server 410A, 410B vialow-throughput I2C buses 442. When the software for the HMC, storagecontroller (and all of its components), switch or storage devices mustbe updated, the software update image is simply pushed from the remoteserver through the high-throughput channels to the final destination or“end host” where the image is loaded and executed. The networkconnection of the SAN and the Ethernet or Fibre Channel connections areat least 100 MB/sec and thus the software update can occur very quicklywith no disruption to normal message traffic or data transfer. When thesoftware for the RPC or PPS must be updated, the software update imageis pushed from the remote server through the high-throughput channels tolocal server 410 a and 410 b where it is stored in memory 416. Thecurrent software image running on the “end hosts” (RPCs or PPPs)serviced by the local server is also stored in memory 416. The localprocessors 414 are configured to using a rack-power control module (RPC)module for allowing a local storage partition, located on a localserver, for controlling a destination storage partition, located on adestination server, by piggybacking a plurality of commands on poweralerts issued by the RPC module, as previously described.

In one embodiment, the various hardware and embodiments, previouslydescribed, are used for controlling a partner partition by using arack-power control module (RPC). The RPC is used for allowing a localstorage partition, located on a local server, to control a destinationstorage partition, located on a destination server, by piggybacking aplurality of commands on power alerts issued by the RPC module. Turningnow to FIG. 5, FIG. 5 is a flowchart illustrating an alternativeexemplary method for controlling partner partitions in a clusteredstorage system. The method 500 begins (step 502) by sending at least onetype of command from a local storage partition to the RPC module (step504). The commands are RPC commands. The RPC commands, sent by thepartition to the RPC, include a destination server identification (ID)and payload data. The payload data includes a hypervisor command. Thepayload data can be variable in size, and have different classes ofcommands. One class could be for controlling the partner partitions,which may include commands such as power off, power on, reboot, forcinga crash dump. Another class could be for querying information about thepartner partitions such as getting the partition OS code level, memorysize, processing capability, etc. The hypervisor commands contain acommand type, a subtype, and a destination identification (ID). Uponreceiving the command from the partition, the RPC module parses thecommand(s) received from the local storage partition (step 506). The RPCmodule is in communication with each hypervisor and storage driversassociated with each of the servers. The payload data, which is parsedby the RPC module from the command(s), is sent to the hypervisorassociated with the destination server (e.g., partner partition) (step508). The method 500 parses the payload data by the hypervisor (step510). The hypervisor directs the parsed payload data to the destinationserver thereby allowing the local partition to control the destinationstorage partition (step 512). The commands include at least one apowering off command, a power on command, and a reboot command. Themethod 500 ends (step 514).

In an alternative embodiment, a running logical partition (LPAR) sendsthe RPC a command (e.g., the RPC commands) via the RPC. The LPAR usesstorage driver code to communicate with the RPC. The RPC parses thecommand and sends the payload data (e.g., the hypervisor commands thatcontains the command type, the subtype, and the destination ID) to aserver's hypervisor via the RPC communicating with the hypervisor of astorage server in the system. The hypervisor parses the hypervisorcommands, and directs the requested action (e.g., such as powering off,powering on, rebooting, etc.), to the target partition.

As will be appreciated by one skilled in the art, aspects of the presentinvention may be embodied as a system, method or computer programproduct. Accordingly, aspects of the present invention may take the formof an entirely hardware embodiment, an entirely software embodiment(including firmware, resident software, micro-code, etc.) or anembodiment combining software and hardware aspects that may allgenerally be referred to herein as a “circuit,” “module” or “system.”Furthermore, aspects of the present invention may take the form of acomputer program product embodied in one or more computer readablemedium(s) having computer readable program code embodied thereon.

Any combination of one or more computer readable medium(s) may beutilized. The computer readable medium may be a computer readable signalmedium or a computer readable storage medium. A computer readablestorage medium may be, for example, but not limited to, an electronic,magnetic, optical, electromagnetic, infrared, or semiconductor system,apparatus, or device, or any suitable combination of the foregoing. Morespecific examples (a non-exhaustive list) of the computer readablestorage medium would include the following: an electrical connectionhaving one or more wires, a portable computer diskette, a hard disk, arandom access memory (RAM), a read-only memory (ROM), an erasableprogrammable read-only memory (EPROM or Flash memory), an optical fiber,a portable compact disc read-only memory (CD-ROM), an optical storagedevice, a magnetic storage device, or any suitable combination of theforegoing. In the context of this document, a computer readable storagemedium may be any tangible medium that may contain, or store a programfor use by or in connection with an instruction execution system,apparatus, or device.

Program code embodied on a computer readable medium may be transmittedusing any appropriate medium, including but not limited to wireless,wired, optical fiber cable, RF, etc., or any suitable combination of theforegoing. Computer program code for carrying out operations for aspectsof the present invention may be written in any combination of one ormore programming languages, including an object oriented programminglanguage such as Java, Smalltalk, C++ or the like and conventionalprocedural programming languages, such as the “C” programming languageor similar programming languages. The program code may execute entirelyon the user's computer, partly on the user's computer, as a stand-alonesoftware package, partly on the user's computer and partly on a remotecomputer or entirely on the remote computer or server. In the latterscenario, the remote computer may be connected to the user's computerthrough any type of network, including a local area network (LAN) or awide area network (WAN), or the connection may be made to an externalcomputer (for example, through the Internet using an Internet ServiceProvider).

Aspects of the present invention have been described above withreference to flowchart illustrations and/or block diagrams of methods,apparatus (systems) and computer program products according toembodiments of the invention. It will be understood that each block ofthe flowchart illustrations and/or block diagrams, and combinations ofblocks in the flowchart illustrations and/or block diagrams, may beimplemented by computer program instructions. These computer programinstructions may be provided to a processor of a general purposecomputer, special purpose computer, or other programmable dataprocessing apparatus to produce a machine, such that the instructions,which execute via the processor of the computer or other programmabledata processing apparatus, create means for implementing thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

These computer program instructions may also be stored in a computerreadable medium that may direct a computer, other programmable dataprocessing apparatus, or other devices to function in a particularmanner, such that the instructions stored in the computer readablemedium produce an article of manufacture including instructions whichimplement the function/act specified in the flowchart and/or blockdiagram block or blocks. The computer program instructions may also beloaded onto a computer, other programmable data processing apparatus, orother devices to cause a series of operational steps to be performed onthe computer, other programmable apparatus or other devices to produce acomputer implemented process such that the instructions which execute onthe computer or other programmable apparatus provide processes forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks.

The flowchart and block diagrams in the above figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof code, which comprises one or more executable instructions forimplementing the specified logical function(s). It should also be notedthat, in some alternative implementations, the functions noted in theblock may occur out of the order noted in the figures. For example, twoblocks shown in succession may, in fact, be executed substantiallyconcurrently, or the blocks may sometimes be executed in the reverseorder, depending upon the functionality involved. It will also be notedthat each block of the block diagrams and/or flowchart illustration, andcombinations of blocks in the block diagrams and/or flowchartillustration, may be implemented by special purpose hardware-basedsystems that perform the specified functions or acts, or combinations ofspecial purpose hardware and computer instructions.

What is claimed is:
 1. A method for controlling partner partitions in aclustered storage system by a processor device in a computingenvironment, the method comprising: using a physical rack-power controlmodule (RPC) module for allowing a local storage partition, located on alocal server, for controlling a destination storage partition, locatedon a destination server, by piggybacking a plurality of commands onpower alerts issued by the RPC module; sending at least one of theplurality of commands from the local storage partition to the RPCmodule, wherein the plurality of commands are RPC commands and include adestination server identification (ID) and payload data that includes ahypervisor command containing a command type, a subtype, and adestination ID; and parsing by the RPC module the at least one of theplurality of commands received from the local storage partition.
 2. Themethod of claim 1, further including connecting the RPC module to aplurality of servers in the clustered storage system.
 3. The method ofclaim 2, further including communicating by RPC module with eachhypervisor and storage drivers associated with each of the plurality ofservers.
 4. The method of claim 3, further including sending payloaddata from the at least one of the plurality of commands that is parsedby the RPC module to the hypervisor associated with the destinationserver.
 5. The method of claim 4, further including: parsing the atleast one of the plurality of commands by the hypervisor, wherein the atleast one of the plurality of commands include the payload data sent tothe hypervisor, directing the parsed payload data to the destinationserver thereby allowing the local partition to control the destinationstorage partition, wherein the plurality of commands include at leastone a powering off command, a power on command, and a reboot command. 6.A system for controlling partner partitions in a clustered storagesystem in a computing environment, the system comprising: a processordevice operable in the computing storage environment, wherein theprocessor device: uses a physical rack-power control module (RPC) modulefor allowing a local storage partition, located on a local server, forcontrolling a destination storage partition, located on a destinationserver, by piggybacking a plurality of commands on power alerts issuedby the RPC module, sends at least one of the plurality of commands fromthe local storage partition to the RPC module, wherein the plurality ofcommands are RPC commands and include a destination serveridentification (ID) and payload data that includes a hypervisor commandcontaining a command type, a subtype, and a destination ID, and parsesby the RPC module the at least one of the plurality of commands receivedfrom the local storage partition.
 7. The system of claim 6, wherein theprocessor device connects the RPC module to a plurality of servers inthe clustered storage system.
 8. The system of claim 7, wherein theprocessor device communicates by RPC module with each hypervisor andstorage drivers associated with each of the plurality of servers.
 9. Thesystem of claim 8, wherein the processor device sends payload data fromthe at least one of the plurality of commands that is parsed by the RPCmodule to the hypervisor associated with the destination server.
 10. Thesystem of claim 9, wherein the processor device: parses the at least oneof the plurality of commands by the hypervisor, wherein the at least oneof the plurality of commands include the payload data sent to thehypervisor, and directs the parsed payload data to the destinationserver thereby allowing the local partition to control the destinationstorage partition, wherein the plurality of commands include at leastone a powering off command, a power on command, and a reboot command.11. A computer program product for controlling partner partitions in aclustered storage system by a processor device, the computer programproduct comprising a non-transitory computer-readable storage mediumhaving computer-readable program code portions stored therein, thecomputer-readable program code portions comprising: a first executableportion that uses a rack-power control module (RPC) module for allowinga local storage partition, located on a local server, for controlling adestination storage partition, located on a destination server, bypiggybacking a plurality of commands on power alerts issued by the RPCmodule; a second executable portion that sends at least one of theplurality of commands from the local storage partition to the RPCmodule, wherein the plurality of commands are RPC commands and include adestination server identification (ID) and payload data that includes ahypervisor command containing a command type, a subtype, and adestination ID; and a third executable portion that parses by the RPCmodule the at least one of the plurality of commands received from thelocal storage partition.
 12. The computer program product of claim 11,further including a fourth executable portion that connects the RPCmodule to a plurality of servers in the clustered storage system. 13.The computer program product of claim 12, further including a fifthexecutable portion that: communicates by RPC module with each hypervisorand storage drivers associated with each of the plurality of servers,and sends payload data from the at least one of the plurality ofcommands that is parsed by the RPC module to the hypervisor associatedwith the destination server.
 14. The computer program product of claim13, further including a sixth executable portion that: parses the atleast one of the plurality of commands by the hypervisor, wherein the atleast one of the plurality of commands include the payload data sent tothe hypervisor, and directs the parsed payload data to the destinationserver thereby allowing the local partition to control the destinationstorage partition, wherein the plurality of commands include at leastone a powering off command, a power on command, and a reboot command.